Pulsed lasers, such as copper vapour lasers, will generally produce pulses of emitted laser light having a duration of the order of 30 nanoseconds (ns). For some applications e.g. picosecond pulse amplification applications, this is too long and, for such applications, it is desired to have pulses of shorter duration, of the order of 10 ns.
This invention relates to apparatus and a method of operating a pulsed laser so as to provide pulses of such shorter duration. The invention is applicable to pulsed lasers in which the gain medium undergoes a rapid transition from gain to absorption, e.g. a pulsed laser using copper vapour as its gain medium.